how to resolve misfire issues in my Toyota Corolla E140 (2006-2013) with code P0302?

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the battery to avoid electrical shorts.
• Ensure the engine is cool before starting work.

2. Replace Spark Plug

• Remove the spark plug wire or ignition coil.
• Use a spark plug socket to carefully remove the old spark plug from cylinder 2.
• Inspect the gap on the new spark plug and adjust if necessary (typically 0.043 inches for a Toyota).
• Install the new spark plug and torque to manufacturer specifications (usually 13 lb-ft).

3. Inspect and Replace Ignition Coil

• If the spark plug replacement does not resolve the issue, remove the ignition coil from cylinder 2.
• Check the coil for cracks or corrosion. Replace if any damage is observed.
• Install the new ignition coil and reconnect the wiring harness.

4. Test and Replace Fuel Injector

• Remove the fuel injector from cylinder 2.
• Test the injector with a noid light to ensure it receives power; replace if faulty.
• Install a new fuel injector and ensure all connections are secure.

5. Compression Test (if necessary)

• If misfire persists, perform a compression test on cylinder 2.
• Use a compression gauge and record the pressure; compare against manufacturer's specifications (usually around 180 psi).
• If compression is low, further diagnosis may be required for possible internal engine issues.